
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>弹出层效果</title>
    <style>
        html,body{height:100%;overflow:hidden;}
        body,div,h2{margin:0;padding:0;}
        body{font:12px/1.5 Tahoma;}
        center{padding-top:10px;}
        button{cursor:pointer;}
        #overlay{position:absolute;top:0;left:0;width:100%;height:100%;background:#000;opacity:0.5;filter:alpha(opacity=50);display:none;}
        #win{position:absolute;top:50%;left:50%;width:400px;height:200px;background:#fff;border:4px solid #f90;margin:-102px 0 0 -202px;display:none;}
        h2{font-size:12px;text-align:right;background:#FC0;border-bottom:3px solid #f90;padding:5px;}
        h2 span{color:#f90;cursor:pointer;background:#fff;border:1px solid #f90;padding:0 2px;}
    </style>
    <script>
        window.onload = function ()
        {
            var oWin = document.getElementById("win");
            var oLay = document.getElementById("overlay");
            var oBtn = document.getElementsByTagName("button")[0];
            var oClose = document.getElementById("close");
            oBtn.onclick = function ()
            {
                oLay.style.display = "block";
                oWin.style.display = "block"
            };
            oClose.onclick = function ()
            {
                oLay.style.display = "none";
                oWin.style.display = "none"
            }
        };
    </script>
</head>
<body>
<div id="overlay"></div>
<div id="win"><h2><span id="close">×</span></h2></div>
<center><button>弹出层</button></center>
</body>
</html>
